纤维率对无腹筋UHPC梁受剪性能的影响研究  

Study on the Influence of Fiber Ratio on Shear Performance of UHPC Beams Without Stirrups

作　　者：张俊超 何拥林 堵健 房宣成 戚家南 ZHANG Junchao;HE Yonglin;DU Jian;FANG Xuancheng;QI Jianan(Sinohydro No.1 Engineering Bureau Co.,Ltd.,Changchun 130033,China;Key Laboratory of Concrete and Prestressed Concrete Structure Ministry of Education,Southeast University,Nanjing 211189,China;National Key Laboratory of Safety,Durability and Healthy Operation of Long Span Bridges,Nanjing 211189,China)

机构地区：[1]中国水利水电第一工程局有限公司,长春130033 [2]东南大学混凝土及预应力混凝土结构教育部重点实验室,南京211189 [3]长大桥梁安全长寿与健康运维全国重点实验室,南京211189

出　　处：《交通科技》2025年第1期39-43,共5页Transportation Science & Technology

摘　　要：为研究纤维对无腹筋超高性能混凝土梁(UHPC)受剪性能的影响,设计6根无腹筋UHPC模型梁,参数包括纤维率和剪跨比,对其进行剪荷载试验,得到试验梁破坏模式和裂缝开展特征,并分析梁体挠度、纵筋应变、裂缝宽度随荷载的发展规律。结果表明,提高纤维率可显著提高无腹筋UHPC梁抗剪承载力与变形能力;正常使用极限状态下,纤维率1%,2%和3%试验梁最大裂缝宽度对应的荷载比无纤维梁分别提高48%,79%,161%;承载能力极限状态下,纤维率1%,2%和3%试验梁抗剪承载力比无纤维梁分别提高133%,235%,322%;中国、法国、瑞士三国规范对无腹筋UHPC试验梁抗剪承载力的预测过于保守。In order to investigate the influence of fiber ratio on the shear behavior of ultra-high-performance concrete(UHPC)beams without stirrups,six UHPC model beams without stirrups were designed,with varying fiber ratios and shear span ratios.The shear-load tests were conducted to investigate their failure modes and crack development characteristics.The law of beam deflection,longitudinal reinforcement strain and crack width with load development was analyzed.The results showed that increasing the fiber ratio significantly enhanced the shear carrying capacity and deformation capacity of UHPC beams without stirrups.Under the normal limit state,the load corresponding to the maximum crack width of test beams with fiber ratio of 1%,2%and 3%was increased by 48%,79%and 161%,respectively,compared with non-fiber beams.The shear capacity of test beams with fiber ratio of 1%,2%and 3%was 133%,235%and 322%higher than that of non-fiber beams.The prediction of the shear capacity of UHPC test beams without stirrups in Chinese,French and Swiss codes is overly conservative.

关 键 词：超高性能混凝土 梁 受剪性能 纤维率 

分 类 号：U444[建筑科学—桥梁与隧道工程]